Automatic train-stop.



G. SBDGWIGK. AUTOMATIG TRAIN STOP. APPLICATION FILED JAN. 4, 1908.

Patented Oct. 6, 1908.

' To all whom it may concern i UNITED STATES PATnnT OFFICE.

HIRAM GEE'SJEDGWVIOK, or MILL vaLLnia cafironnm au'rom'rrc TRAIN-STOP.

'Be' it known that I, HIRAM G. Snnowron, a citizen of the United States of America, and a resident of Mill Valley, county of Marin, State of California, have invented certain new and useful Im rovements in Automatic Train-Stops, of which the following is a full and clearspecification, referencebeinghad to the accompanying drawing, in Which- Figure 1 is a vertical sectional view' partly Y in side" elevationfof vent-valve mechanism constructed according to my present invention. Fig. 2 is a vertical sectional view on the line 2 -2 of Fig. ,1. Fig. 3. is a vertical sectional view on the line 33 of Fig.1.

- This invention has special relation to that.

class of automatic vent;.valves which upon the arrival of the locomotive at a danger point are automatically actuated to vent the train-pipe and thus apply the brakes, the valve being so constructed that after each actuation it normally closes, thus restoring the apparatus 'to "operative condition and putting the brake mechanism again under the control of the-engineer. Examples of this apparatus are. found my fermer patents.

The'object of the present improvements is to provide automatic devices which while not interfering withthe restoration of the valve-operating devices to normal operative position will at the same time prevent the automatic restoration of the brake apparatus to the controlofthe engineer but will require on. the part of the engineer some s ecial act" of manual manipulation to put the rak ing apparatus back into his control .through his controller valve. Theobject of thus permitting the vent-valve to be restored 'to normally closed operative condition while preventing the engineer from again getting control of the brake system without some special act on'his part other than the mere operation ofthe engmeers valve is to prevent the train automatically starting again after the automatic pump means on the locomotivehave restored the pressure in the'train-pipe.

Under my former systems it will be observed that after closing of the vent-valve the automatic pump devices on the locomo-.

'tive'would automaticallyrelease the brakes as soon as the pressure was again restored in the tram-pipe, so that 1f the engineer had become incapacitated by illness or death or had left his post with the throttle left open the train would again proceed on its way as soon Specification of Letters Patent.

. Application filed January 4, 190.8. Serial No..409,302.

Patented as. e, 1eos.

as the pressure in the train-pipe was raised sufliciently to release the brakes.- Thiswould obviously 1n many cases result'in disaster and I have, therefore, devised means whereby the train would be caused to remain at a standstill even though the throttle be wide open until a person in the cab performs a special act to permit the train-pressure to be again restored by the automatic devices.

In the present embodiment of this improvement I propose employing a supplemental or auxiliary vent-valve which will be actuated after the main vent is opened and which will be held open after the main ventis closed and until a person in the cab closes it by some 'manu'al effort, as more fully hereinafter set forth.

Referring to the drawing annexed by reference characters, Mdesignates a portion of the'train-pipe of the air-brake mechanism which is connected to a valve-chest I) having an outlet port c,'this port being controlled .by a circular rotatable valve d'- which is attached to the shaft 0 of a suitable clockworkmotor. This valve d is provided with an elongatcdport d circular in form and concentric with the shaft 0, the forward end-portion (l of this port being abruptly narrowed down to a slit while themain portion of the port is sufficiently wide to entirely uncover the escape port (2 when it passes over said escape portin the rotation of the valve. y

Onthe shafte. is mounted a cam 7'', this cam being so shaped that at a predetermined point in the rotation of the shaft it will bear against a brake-lever g and cause said lever to press upon the periphery of the brake-wheel h mounted on one of the shafts of the clockwork motor, preferably the shaft carrying the fan in. 1 The devices for starting and stopping the motor consist essentially of a vertical gravisaid contact plate being insulatedly carried on the shaft 6'.

holding up the rod Z away from the fan The cam 0 provides for after the armature lever is dropped through the breaking of its circuit and until an en tire revolution of the valve-shaft e is obtained; when a full revolution is obtained the rod Z drops oil the shoulder of the cam and stops the fan.

I do not make any claim on the foregoing devices in this application as they are covered by my co-pending application Serial No. 381,467, filed June 29th, 1907.

I. apply my present improvements to mechanism of the foregoing type by mounting on the shaft 6 an additional cam 4 and so shape said cam that just before the main valve d is closed said cam will push stem 5 ,of the supplemental valve 6 contained in a. 'i'alvecasing 7 and thus open said valve.

A latch bolt 8 Will normally engage a notchmr. lug

. on said stemand hold the same open after the valve has passed the stem 5. A spring 9 within the casing 7, together with the air pressure therein, will normally hold the valve 6 closed. The valve chamber 7 is connected by a suitable pipe 10 with the trainpipe through the valve chest I). The automatic latch bolt 8 is connected to a pull-cord or wire 11 which may be extended forward to the cab where it may be Within convenient reach of the engineer or fireman.

lVith the supplemental vent device it will be observed that the train-pipe will be still vented after the main valve is closed so that it will be impossible to release the brakes until the engineer or some other person pulls the cord 11 and releases and closes the supplemental vent, after which the automatic I pump on the locomotive will restore the pressure in the train-pipe and release the brakes automatically; With this device therefore it Will be impossible for the train to start up automatically after an actuation of the automatic vent so that even though the throttle be open the train will remain at a standstill unless the engineer is at his post and is capable of making the special eilort required to restore the braking apparatus to his control.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In combination with automatic trainstopping devices embodying means for opening and closing a. main vcnt,'of a supplemental vent and means for opening and holding open the same after the main vent is closed, and means for manually closing this supplemental vent.

2. In combination with automatic trainstopping mechanism embodying am'ain vent and. means for automatically opening and closing the same, of automatic means for preventing the automatic restoration of the brake mechanism to the control of the engineer, and manual means for releasing this latter preventing means,

3. The combination of automatic trainstopping devices, of means operated thereby for automatically preventing the release of the brakes after the automatic devices have applied them, and manual means within the control of the engineer for releasing said automatic preventing means and thus restoring the brake mechanism to the control of the engineer. 1

In testimony whereof I hereunto atiix my signature in the presence of two Witnesses this 9/1- day of December, 1907.

HIRAllI GEE SEDG-WIOK.

lVitnessos 2 S. H. Ronnnrs, IIENRIETTA Ronnn'rs. 

